/* 重置和基础样式 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Arial', sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #f8f9fa;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* 头部导航 */
.header {
    background: #fff;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 20px;
}

.logo h1 {
    color: #2c3e50;
    font-size: 1.8rem;
}

.nav ul {
    display: flex;
    list-style: none;
    gap: 2rem;
}

.nav a {
    text-decoration: none;
    color: #333;
    font-weight: 500;
    transition: color 0.3s;
}

.nav a:hover {
    color: #3498db;
}

.header-actions {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.search-box {
    display: flex;
}

.search-box input {
    padding: 0.5rem;
    border: 1px solid #ddd;
    border-radius: 4px 0 0 4px;
    outline: none;
}

.search-box button {
    padding: 0.5rem 1rem;
    background: #3498db;
    color: white;
    border: none;
    border-radius: 0 4px 4px 0;
    cursor: pointer;
}

.cart-icon {
    position: relative;
    font-size: 1.5rem;
    cursor: pointer;
}

.cart-icon span {
    position: absolute;
    top: -8px;
    right: -8px;
    background: #e74c3c;
    color: white;
    border-radius: 50%;
    width: 20px;
    height: 20px;
    font-size: 0.8rem;
    display: flex;
    align-items: center;
    justify-content: center;
}

/* 横幅区域 */
.banner {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 4rem 0;
    text-align: center;
}

.banner-content h2 {
    font-size: 3rem;
    margin-bottom: 1rem;
}

.banner-content p {
    font-size: 1.2rem;
    margin-bottom: 2rem;
}

.cta-button {
    background: #e74c3c;
    color: white;
    padding: 1rem 2rem;
    border: none;
    border-radius: 5px;
    font-size: 1.1rem;
    cursor: pointer;
    transition: background 0.3s;
}

.cta-button:hover {
    background: #c0392b;
}

/* 筛选区域 */
.filters {
    background: white;
    padding: 2rem 0;
    margin: 2rem 0;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.filters h3 {
    margin-bottom: 1rem;
    color: #2c3e50;
}

.filter-options {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
}

.filter-options select {
    padding: 0.5rem;
    border: 1px solid #ddd;
    border-radius: 4px;
    background: white;
    cursor: pointer;
}

/* 商品网格 */
.products-section {
    padding: 3rem 0;
}

.products-section h2 {
    text-align: center;
    margin-bottom: 2rem;
    color: #2c3e50;
}

.products-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 2rem;
}

/* 商品卡片 */
.product-card {
    background: white;
    border-radius: 10px;
    overflow: hidden;
    box-shadow: 0 4px 15px rgba(0,0,0,0.1);
    transition: transform 0.3s, box-shadow 0.3s;
}

.product-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 25px rgba(0,0,0,0.15);
}

.product-image {
    width: 100%;
    height: 200px;
    object-fit: cover;
}

.product-info {
    padding: 1.5rem;
}

.product-title {
    font-size: 1.2rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
    color: #2c3e50;
}

.product-description {
    color: #666;
    margin-bottom: 1rem;
    font-size: 0.9rem;
}

.product-price {
    font-size: 1.3rem;
    font-weight: bold;
    color: #e74c3c;
    margin-bottom: 1rem;
}

.product-rating {
    color: #f39c12;
    margin-bottom: 1rem;
}

.add-to-cart {
    width: 100%;
    padding: 0.75rem;
    background: #3498db;
    color: white;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    transition: background 0.3s;
}

.add-to-cart:hover {
    background: #2980b9;
}

/* 购物车侧边栏 */
.cart-sidebar {
    position: fixed;
    top: 0;
    right: -400px;
    width: 400px;
    height: 100vh;
    background: white;
    box-shadow: -2px 0 10px rgba(0,0,0,0.1);
    transition: right 0.3s;
    z-index: 1001;
    display: flex;
    flex-direction: column;
}

.cart-sidebar.active {
    right: 0;
}

.cart-header {
    padding: 1.5rem;
    border-bottom: 1px solid #eee;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.close-btn {
    background: none;
    border: none;
    font-size: 1.5rem;
    cursor: pointer;
    color: #666;
}

.cart-items {
    flex: 1;
    overflow-y: auto;
    padding: 1rem;
}

.cart-item {
    display: flex;
    align-items: center;
    padding: 1rem;
    border-bottom: 1px solid #eee;
    gap: 1rem;
}

.cart-item-image {
    width: 60px;
    height: 60px;
    object-fit: cover;
    border-radius: 5px;
}

.cart-item-details {
    flex: 1;
}

.cart-item-title {
    font-weight: 600;
    margin-bottom: 0.25rem;
}

.cart-item-price {
    color: #e74c3c;
    font-weight: bold;
}

.cart-item-quantity {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    margin-top: 0.5rem;
}

.quantity-btn {
    width: 25px;
    height: 25px;
    border: 1px solid #ddd;
    background: white;
    cursor: pointer;
    border-radius: 3px;
}

.remove-item {
    color: #e74c3c;
    background: none;
    border: none;
    cursor: pointer;
    font-size: 1.2rem;
}

.cart-footer {
    padding: 1.5rem;
    border-top: 1px solid #eee;
}

.cart-total {
    font-size: 1.3rem;
    font-weight: bold;
    margin-bottom: 1rem;
    text-align: center;
}

.checkout-btn {
    width: 100%;
    padding: 1rem;
    background: #27ae60;
    color: white;
    border: none;
    border-radius: 5px;
    font-size: 1.1rem;
    cursor: pointer;
    transition: background 0.3s;
}

.checkout-btn:hover {
    background: #219a52;
}

/* 模态框样式 */
.modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0,0,0,0.5);
    z-index: 1002;
}

.modal.active {
    display: flex;
    align-items: center;
    justify-content: center;
}

.modal-content {
    background: white;
    padding: 2rem;
    border-radius: 10px;
    width: 90%;
    max-width: 400px;
    position: relative;
}

.modal .close {
    position: absolute;
    top: 1rem;
    right: 1.5rem;
    font-size: 1.5rem;
    cursor: pointer;
}

.auth-tabs {
    display: flex;
    margin-bottom: 1.5rem;
    border-bottom: 1px solid #eee;
}

.tab-btn {
    flex: 1;
    padding: 0.75rem;
    background: none;
    border: none;
    cursor: pointer;
    border-bottom: 2px solid transparent;
}

.tab-btn.active {
    border-bottom-color: #3498db;
    color: #3498db;
}

.auth-form {
    display: none;
}

.auth-form.active {
    display: block;
}

.auth-form input {
    width: 100%;
    padding: 0.75rem;
    margin-bottom: 1rem;
    border: 1px solid #ddd;
    border-radius: 5px;
}

.auth-form button {
    width: 100%;
    padding: 0.75rem;
    background: #3498db;
    color: white;
    border: none;
    border-radius: 5px;
    cursor: pointer;
}

/* 页脚 */
.footer {
    background: #2c3e50;
    color: white;
    text-align: center;
    padding: 2rem 0;
    margin-top: 3rem;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .header .container {
        flex-direction: column;
        gap: 1rem;
    }
    
    .nav ul {
        gap: 1rem;
    }
    
    .banner-content h2 {
        font-size: 2rem;
    }
    
    .products-grid {
        grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
        gap: 1rem;
    }
    
    .cart-sidebar {
        width: 100%;
        right: -100%;
    }
    
    .filter-options {
        flex-direction: column;
    }
}

@media (max-width: 480px) {
    .products-grid {
        grid-template-columns: 1fr;
    }
    
    .banner-content h2 {
        font-size: 1.5rem;
    }
    
    .container {
        padding: 0 10px;
    }
}